Australia's Wimmera-Mallee farmers are hoping that the rain over the weekend should not impact the quality of grain.

The harvest was in full swing but has been halted by rain of between five and 10 millimetres in many parts but up to 20 millimetres fell in some areas.

Ouyen farmer Ian Hastings says how quickly the crops dry out is more important than the amount of rainfall received.

However, he says with the current low wheat prices and poor protein levels, farmers cannot afford to have grain downgraded.

"Look, we are all very, very nervous about grain sprouting after last year ... and even though there was only a small amount, because it was keeping the crop wet for quite a number of hours, there is still some concern about whether there will be any damage from it," he said.